The behaviour that you mention often appears when the root_url in config.php is wrong.

Usually the update should not interfere with that, but maybe the config.php was substituted?

Sorry, only had a look now, and no, that is not the same behaviour.

Have a look at the manual! It is a really valuable source for information. Here some helpful links:Manual (EN) | Question Types | [url=https://manual.limesurvey.org/Workarounds[/url]
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I have check my PHP installation and it seems OK. There are no errors in the logs and the php.ini file seems OK.

So I went to the admin.php and update/updater.php and then to the database, where I found that DBVersion was still to 142 despite all messages on screen. So I updated the value to 143 and now I get the login screen. However, no matter which username/password combination I use, I get a blank screen in return.

I do not remember clearly which version I had before, but I think it was 1.82+